Punch and die assembly for forming a cluster of covers



April 27, 1965 E. L. MIDGLEY ETAL 8 PUNCH AND DIE ASSEMBLY FOR FORMING A CLUSTER 0F COVERS Filed Sept. 26, 1961 4 Sheets-$heet 1 April 1965 E. MIDGLEY Ei-AL 3,180,191

PUNCH AND DIE ASSEMBLY FOR FORMING A CLUSTER 0F COVERS Filed Sept. 26, 1961 4 Sheets-Sheet 2 56 Q ..l6 I Ipm I 74 x 96 QQ 78 R F|G.4

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l0 M/06Z Mama/1%, (#00:: BY Jam/4 HAL Mk0 WW W W ATTORNEYS I April 27, 1965 MIDGLEY ETAL PUNCH AND DIE ASSEMBLY FOR FORMING A CLUSTER OF COVERS Filed Sept. 26, 1961 4 Sheets-Sheet 3 FIG. 3

\\7O INVENT R.

me LlM/OGEZ IWIWA'PA. W005 JOHN A. l'I/lYWfiRD BY Z'I' ORNEYS April 1965 E. MIDGLEY EI'AL PUNCH AND DIE ASSEMBLY FOR FORMING A CLUSTER OF COVERS Filed Sept. 26, 1961 4 Sheets-Sheet 4 IWW a, m #0 R MAM A m WM Uited States Patent 3,130,191 PUNCH AND BE ASSEWLY FQR FQRMENG A QLUSTER 6F CQVERS Eric L. Midgiey, Danvers, Norman A. Rhodes, l /altham, and .lohn A. Hayward, North Weyrnonth, Mass, assigu= ors to Sweetheart Plastics, Inc, a corporation of Maryland Filed Sept. 26,1961, Ser. No. 146,341 9 Claims. (61. 83-137) This invention relates to disposable plastic container covers and more particularly comprises a novel method and apparatus for manufacturing a cluster of interconnected plastic lids.

Recently machines and equipment have been developed to simultaneously fill a plurality of cups with beverage and thereafter to cover the cups to maintain and preserve the quality of said beverage for sale at parks, fairs and other like large gatherings. The need for such equipment will be appreciated upon consideration of the fact that a relatively large number of such cups of beverage must be dispensed in a relatively short period of time. In order to take full advantage of the sales opportunities afforded, the supply of filled cups must be capable of being quickly replenished and such equipment makes it possible for the vendor to simultaneously provide a plurality of such cups. Briefly, this is accomplished as follows: trays containing twelve or more empty cups ar placed in a dispensing machine which successively discharges ice and prepared beverage into each of these cups. thereafter, the trays are moved from the beverage filling position to a station Where the lids are placed on each of the filled cups. The cups may be covered very rapidly if the lids are formed as a cluster connected together by tabs or other means so that in one operation lids may be placed over all of the cups in the tray. Closing of the cups may then be accomplished by a machine which presses the lids firmly on the cups and thereafter severs each of the lids from the others in the cluster.

Heretofore the apparatus for filling and closing cups described briefly above has not been fully exploited as the clusters of lids for closing the cups have not been available. While the general design of the lid cluster is dictated by the arrangement of the cups in the trays, plastic manufacturers have been unable to produce the clusters at low enough prices to make them economically practical.

The primary object of this invention is to provide a method of inexpensively producing clusters of lids in large quantity.

Another important object of this invention is to provide a punch and die assembly which may sever a plurality of lids in the form of a connected lid cluster from a sheet and accommodate the scrap material severed from between adjacent lids.

Another important object of this invention is to provide a punch and die assembly which can accommodate without alteration clusters of difierent sizes of lids.

Yet another object of this invention is to adapt existing high speed machinery to perform the cutting operation required to remove the cluster from the sheet.

Still another important object of this invention is to provide a cluster of lids wherein each of the lids readily aligns itself with the particular cup to be covered an has a snap fit with the cup.

The cluster of lids about which this invention is centered includes a plurality of lids formed by any suitable process in a sheet of material. Each of the lids includes a downwardly flared wall which is adapted to extend over and engage the rim or lip of the cup on which the lid is mounted. Extending outwardly from the bottom of each lid is a margin or flange oriented generally normal to Bjhhdfil Fatented Apr. 27, 1965 the lid axis and cut from the unformed portion of the sheet in which the lids are formed. The several lids are arranged in longitudinal and transverse rows that may be normal to one another, depending of course upon the arrangement of cups held in the tray for filling, and are spaced apart a distance which exceeds the sum of the width or the margins of adjacent lids. The margins of adjacent lids in the transverse and longitudinal rows are secured together by tabs which are also cut from the unformed portion of the sheet in which the lids are originally formed. Thus, the lids, margins and tabs when severed from the sheet make up a lace-like pattern.

The individual lids of the cluster are provided with the wide flared skirts that fit over the rims of the cups and each skirt is formed with an undercut portion at the top which snaps over the rolled rim of the cup. Thus,

the flared skirt serves as a guide to position the lid in place and the undercut portion grips the rim to retain the lid in place after it is pushed downwardly on the cup.

In detail, the lid cluster when out from the sheet has a scalloped outer margin with the scallops along each side formed by substantially of arc of the lid margins lying in one of the outer rows of the cluster. The scallops are connected by straight edges formed by the sides of tabs joining the margins about the lids. Inwardly of the edges of the cup cluster are openings or cutouts each of which is defined by a portion of the periphery of four adjacent lids and the tabs which join' them.

Connected clusters of lids are produced in number as follows: first, as an independent step, a sheet of plastic material is passed through a forming machine which shapes the lids in parallel transverse rows in the sheet. The sheet with the rows of lids formed in it is fed to a machine which severs several rows of lids as a connected cluster from the sheet, leaving a surrounding skeleton and separate scrap cutouts, and the machine feeds the skeleton and cluster in one direction and the scrap cutouts in another. Thus, in accordance with this invention, the severing of the cluster of lids may be conducted as an independent step from the lid forming operation. Preferably, the sheet with the rows of lids formed in it is fed continuously and directly to the trimming machine which severs the clusters of lids.

A punch and die assembly forms part of the trimming machine for cutting the cluster of lids from the sheet. The die includes a plurality of openings'or recesses formed in longitudinal and transverse rows spaced to receive the lids formed in the sheet. Joining the major openings or recesses which receive the lids are shallow recesses which conform in shape to the tabs to be cut in the sheet, which join the lids and more particularly the margins about'the lids. Thepunch includes a plurality of circular lid punches equal in number to and aligned with the major recesses in the die that receive the lids. The punch also includes short connecting punches aligned with the shallow recesses of the die and which extend between and merge smoothly with the lid punches. Thus,

when the punch and die operate, they simultaneously form or sever the periphery of the cluster as Well as the internal cutouts. To dispose of the scrap interior cutouts, a plurality of openings are formed in the punch backing plate and are aligned with and extend beyond the edges of each of the cutout shapes defined in the punch by the edges of the lid punches and the connecting punches. The cutouts are pushed through the openings in the backing plate and are discharged from the machine by a forced draft behind the backing plate and/or by a moving cog belt behind the backing plate to strip the scrap.

These and other objects, features and advantages of this invention will be better understood and appreciated from the following detailed description of one embodi ment thereof, selected for purposes of illustration and shown in the accompanying drawing, in which:

FIG. 1 is a side elevation of a trim press machine modified in accordance with this invention;

FIG. 2 is a view in perspective of a cluster of lids cut from the machine of FIG. 1;

FIG. 3 is an enlarged cross-sectional view of the punch and die assembly in the machine of FIG. 1;

FIG. 4 is a view similar to FIG. 3 but in reduced scale, showing the punch, die, and platen in their open positions;

FIG. 5 is a view in perspective of the punch shown in FIGS/3 and 4;

FIG. 6 is a perspective view of a portion of the die shown in FIGS. 3 and 4; and

FIG. 7 is a fragmentary cross-sectional view of two of a cluster of lids positioned on the rims of a pair of cups.

The machine shown in FIG. 1 is basically a standard trim press. However, some of its parts as well as its operation have been modified to perform the new and special functions required. Briefly, the press assembly includes a frame 10 supporting a fixed bed 12, a moving ram 14 and a floating platen 16. The ram is driven by a motor 18 through a V-belt and pulley system suggested in part at 20' and a crank 22. Many of the details of the press which are of standard design are omitted for purposes of clarity and as they form no part of this invention.

Mounted on top of the frame it) is a bonnet 24 over which the sheet material to be trimmed is fed on rollers 26 to the location of the bed, platen and ram. A mechanism for feeding the sheet material over the bonnet and through the press area is not shown as it is of standard design, but a speed control 28 and chain and sprocket assembly 30 are suggested which drive the feeding mechanism and is shown in turn to be driven by the motor 18.

In FIG. 1 it will be noted that a sheet 32 extends over the bonnet 24 and is being fed in the direction of arrows 34. The sheet 32 before reaching the bonnet 24 has been subjected to a forming operation that shapes the individual lids 36 in the sheet. However, the individual lids have not in any way been severed or trimmed from the sheet. The sheet with the lids formed in it is fed downwardly through the frame 10 between the fixed bed 12 sheet 32 may be fed continuously to the machine, that is, to the inlet side of the bonnet so long as room is afforded on the right side of the machine as shown in FIG. 1 to allow the sheet to gather during periods when the punch and die assembly operate and the sheet is stationary.

The function of the machine shown in FIG. 1 is to stamp or trim from the unbroken sheet a cluster of lids of the variety shown in FIG. 2. It will be noted in that figure that the individual lids 36 include a top wall 37 and a depending flared skirt 39 surrounded by an annular margin 38 and that the margins of adjacent lids are connected together by tabs 40. Thus, the cluster of lids shown in FIG. 2 has in outline a scalloped margin wherein the scallops are defined by approximately 180 of the periphery of the margin 38, and the scallops are joined by the side edgesof the tabs 40. Cutouts 42 are severed from the interior portion of the sheet and are defined by the arcs of adjacent lids and the edges of the tabs. Thus,

' each cutout-42 in FIG. 2 is defined by four arcs 44 each a little less than 90, and four joining straight edges 4-6 defined by the side edges of the tabs. In thecluster of twelve lids shown in FIG. 2 there are six cutouts of scrap,

be appreciated that the sheet with the lids initially formed in it has straight parallel side edges and an imperforate surface. In FIGS. 3 and 4, a die holder 56 is shown to carry a die backing plate 52 secured in place by machine screws 54 having their heads 56 countersunk in bores 58 in the surface of the die backing plate. The die holder 59 in use is mounted on the fixed bed 12 of the trim press. A die 69 mounted on the backing plate is shown sectioned at its upper and lower halves along two parallel planes in FIGS. 3 and 4. In the lower half of the drawing it will be noted that cavities 62 are formed in the die and extend through its cross section. Each of the recesses provided in the die is adapted to receive one of the lids formed in the sheet 32. The cavities or recesses 62 formed in the die are joined by shallow recesses 64 which are sized to serve as blanks for the cutting of the tabs 49. This arrangement is shown clearly in FIG. 6.

The punch assembly shown in FIGS. 3-5 includes a punch holder 76 which in use is secured to the moving ram 14 of the press. The punch holder supports a scrap chute plate 74 provided with vertically oriented chutes '73 formed in its left face 76 as viewed in FIGS. 3 and 4 that extend throughout the height of the plate. The chutes 73 formed in the plate convey scrap cutouts 42 which are cut from the sheet, as will be more specifically described below. The scrap plate 74 secured to the holder 7% by means of the machine screws 80 in turn supports the punch backing plate 82 secured by means of machine screws 34 having counter sunk heads virtually identical to the screws which support the die backing plate 52. The backing plate 82 carries a plurality of cylindrical lid punches 86 and connecting punches 88 which are aligned respectively with the cavities 62 and shallow recesses 64 in the die. The punch backing plate 32 is provided with a plurality of openings 90 aligned with the spaces between the lid and connecting punches mounted on its face. The openings 99 register with the slotsor chutes 78 in the scrap plate '74 to convey the separated cutouts from the sheet 32 of lids as the cluster is trimmed.

The general assembly of the punch and die is compieted by the floating platen 16 which has a large rectangular opening ?4 formed in its center and aligned with the punch and die, and supports a stripping plate 96 having a somewhat smaller rectangular opening )8. The opening 98 in the stripping plate is just large enough to receive the punches and is somewhat smaller than the area of the punch backing plate 82 and the die 60.

In FIG. 5 the punch and backing plate assembly is shown in detail. The backing plate 82 supports twelve cylindrical punches 86, one of which is removed in the drawing, each held in place by machine screws 100 threaded in the plate openings 102. The cylindrical punches 86 are provided with two or more grooves 104 in their cylindrical wall, the number being determined by the particular position of the punch on the plate. The four corner cylindrical punches 86 are provided with two grooves 194', the other outside cylindrical punches 86" are provided with three grooves 104", and the two interior cylindrical punches 86' are provided with four such grooves. The grooves are spaced about the cylindrical surfaces of the punches 90, center to center. The ends of the connecting punches 88 fit snugly within the grooves 104 and are screwed in place on the backing plate 82 by machine screws 166.

The cylindrical and connected punches mounted on the backing plate in the manner described above form cutting edges which conform in outline to the perimeter of the cluster of lids and the cutouts 42, shown in FIG. 2; Thus, the endless cutting edge 108 defined by approximately of arc of each cylindrical punch 86" V V and 270 of arc of cylindrical punches 86' and by the outer side edges of the connecting punches 88 seversthe outline of the cluster from the sheet, leaving in the sheet' a generally frame-like skeleton. The scrap cutouts 42 are cut in the sheet by the six separate and endless cutting edges 110 defined by approximately 90 of are from each of the interior cylindrical punches 86" and 90 of arc from the side and corner peripheral cylindrical punches; and further defined by the inside edge of each of the connecting punches 88. Thus, the con tinuous cutting edge 108 serves to sever the perimeter of the cluster while the several endless cutting edges 110 sever the cutouts from the sheet.

In FIG. 5 the relative positions of the openings 93 in the backing plate and the interior cutting edges 11% are shown. The entire margin or cutting edge lit) for severing each cutout 42 lies within the projected area of the openings 90. Thus, the cutouts 42 when severed from the sheet pass freely into the passages 90 without binding against the peripheral walls. In this manner, the cutouts pass through the passages 90 freely and enter the chutes 78 in the scrap plate 74 and move downwardly out of the machine as suggested in FIG. 1. The downward travel of the cutouts 42 in the chutes 7'8 may be aided by a belt and pulley suggested by phantom lines 128 in FIG-S. 3 and 4.

Disposed in each of the cavities 62 of the die 66 is a saucer-shaped lid ejector 122 having a skirt 124 in sliding engagement with the margins of the cavity 62. The lid ejectors 122 each includes a boss 125 that extends rearwardly from the base of the saucer and which carries a pin 128 that serves as a guide by virtue of its registration with the walls of sleeve 130 for axial movement of the ejector in the recess or cavity 62 of the die. Coil springs 132. surround the boss 126, bear against seats formed in the plate 52, and urge the ejectors out of the cavities 62 in the direction of the punch.

In the lower portion of FIG. 3 the floating platen carrying the stripping plate 96 and the punch holder 70 are shown in position to sever the cluster of FIG. 2 from the sheet 32. It will be noted in the upper portion of FIG. 3 that the connector punch 88 is disposed within the slot as of the die to sever the sides of the tab 46. Also, the cylindrical punches 86 have entered the corresponding circular openings 62 of the die to sever the lids about their periphery in spaced arcs. After the cuts have been made, the ram and floating platen return to the position shown in FIGS. 1 and 4 so that the stripping plate and punch are spaced from one another and from the die. The stripping plate causes the sheet to free itself from the punch after the cluster has been cut. The cutout scraps 42 however are carried through the striping plate $6 rearwardly with the punch and as described pass through the openings 99 in the punch backing plate and downwardly through the passages 73 in the scrap plate.

V-lhen the punch and die are separated as in FIG. 4, the drive 3%? through standard actuators (not shown) move the sheet 32 downwardly in the direction of arrows 34 to feed an unpunched part of the sheet between the punch and die. At the same time, the skeleton of the severed cluster, which remains connected to the uncut part of the sheet, is carried from the machine on conveyor 14h. Simultaneously, the severed cluster 142 is freed from the die by the action of the ejectors on the lids and is deposited loosely on the conveyor 140. The cluster maybe removed either manually or automatically further along on the conveyor.

In FIG. 7, the lids are shown in detail, 'and in the manner in which they fit over the rims of the cups that they cover. It will be recalled from the introductory remarks that the lids in the cluster are normally deposited manually over the cups in the tray and thereafter the clusterof lids is pressed downwardly onto the filled cups. To enable an operator to position the cluster on the cups quickly without the exercise of great care, the

skirt 39 of each lid has a pronounced flare so that the lids vertically align themselves with the cups in the tray.

sary to provide some means of locking the lids in place on the rims of the cups, as the frictional engagement of a skirt on the rim of itself is inadequate to retain the lid in place. In accordance with this invention an undercut section 156 is provided at the top of each skirt 39, which is adapted to snap on or below the rolled rim 152 of the cup 154 to retain the lid in place. Above the undercut section 15% is an inwardly open head 15% which receives the rolled rim 152 of the cup.

Having described the several features of my invention in detail, its numerous .advanta es will be apparent to those skilled in the art. For example, because the method of this invention may be practiced on high speed machinery such as trim presses, clusters may be produced in volume economically. Furthermore, the punch and die assembly invented is suitable for use with cup lids of a wide variety of sizes' So long as the lids fit within the ejectors, the punch and die assembly may be used. If this one condition is satisfied, the punch and die assembly may be used and the only change which results with lids of diiierent size is in the width of the margin which surrounds each lid; that is, the larger the lids, the smaller the flanges or margins which are cut from the sheet. it will also be apparent that the clusters may be molded svith' substantially any number of lids determined only by the arrangement and number of the punch and die parts. The lids themselves are self aligning and lock on the cup rims. Their shape enables them to be used with cups of virtually any shape limited only to a specific rim diameter.

From the foregoing, those skilled in the art will appreciate that many modifications may be made of the invention descibed without departing from the spirit of my invention. There, we do not intend to limit the breadth of this invention to the specific embodiment illustrated and described. Rather, it is our intention that the breadth of this invention be determined by the appended claims and their equivalents.

What is claimed is:

1. A punch assembly comprising a backing plate, a plurality of parallel longitudinal rows of openings extending through said plate with the adjacent openings in adjacent rows aligned normal to the rows to form transverse rows of openings, a plurality of punches secured to one side of the plate and centered between the longitudinal and transverse rows of openings with the edges of the punches overlying the adjacent openings, and com nector punches secured to the backing plate and interconnecting the adjacent punches in rows parallel tothe longitudinal and tran verse rows of openings, said punches and connector punches forming a plurality of endless cutting edges on the assembly.

2. A punch assembly comprising a backing plate, a

plurality of circular punches secured to one side of the backing plate and aligned in mutually perpendicular longitudinally and transverse rows, connecting punches secured to the plate between the circular punches and interconnecting the edges of the adjacent circular punches, and means definiru holes in the backing plate aligned with the arcs of the adjacent circular punches and the edges of the connecting punches.

3-. A punch and die assembly comprising a die having at least two major recesses formed therein, a third recess formed in the die and interconnecting the major recesses, a punch backing plate movable toward and away from the die, a pair of punches mounted on the plate and aligned with the major recesses formed in the die and adapted to enter said recesses when the plate is moved to ward the die, and a connecting punch secured to the plate and interconnecting the two recited punches, said connecting punch being aligned with the third recess in the die and registering with the recess when the plate moves toward the die, whereby a sheet disposed between the punch and die will be formed with a pair of blanks in the shape of the major recesses interconnected by a tab integral with the blanks in the shape of the third recess when the plate is moved to register with the die.

4. A punch and die assembly adapted to sever from a sheet a plurality of cup lids in a cluster previously fromed in thesheet comprising a die having a plurality of recesses each adapted to receive one lid formed in the sheet, a backing plate, a plurality of punches mounted on the plate for making spaced arcuate cuts about the periphery of each lid in the recesses in the die, and additional punches secured to the plate between the first recited punches and interconnecting the punches for making cuts in the sheet joining the ends of adjacent arcuatelcuts about adjacent lids to leave a tab joining the adjacent lids.

5. An assembly as defined in claim 4 further characterized by openings formed in the plate and overlapping the edges of adjacent punches to receive the scrap severed from the sheet from between the lids.

6. Apparatus for serving from a sheet a cluster of cup lids previously formed in the sheet in longitudinal and transverse perpendicular rows comprising a die having a plurality of recesses each larger than a lid aligned in rows conforming to the orientation of the lids in the sheet for receiving the lids formed in the sheet, a punch assembly having an endless cutting edge registering with the recesses for trimming from the sheet the margin of the sheet about the cluster of lids and having a plurality of smaller endless cutting edges, each registering with a plurality of adjacent recesses for trimming cutouts between adjacent lids and leave tabs joining each of the adjacent lids, and means for directing the cluster of lids and the margin of the sheet in one direction and the cutouts in another direction.

7. Apparatus for servinga cluster of interconnected lids from .a sheet in which the lids are formed comprising a die adapted to receive each of the lids while the lids are connected as part of a sheet, a platen having a central opening therein and movable toward and away from the die, a punch assembly-movable toward and away from the die and sized to pass through the central opening in the platen when moved toward the die a plurality of endless unconnected cutting edges forming part'of the punch assembly and cooperating with the die for trimming unconnected scrap cutouts from the sheet between the individual lids while leaving tabs interconnecting adjacent lids and a stripping plate secured to the platen for removing the sheet from the punch assembly after the cluster is cut.

8. Apparatus as defined in claim 7 further characterized by means mounted on the die for ejecting the cluster from the die after the punch has operated.

9. Apparatus for serving from a sheet a cluster of cup lids previously formed in the sheet comprising a die having a plurality of recesses adapted to receive simultaneously the lids formed in the sheet, and a punch assembly movable towards and away from the die and having a plurality of endless unconnected cutting edges 00- operating with the recesses for trimming unconnected scrap cutouts from the sheet between adjacent lids while leaving tabs interconnecting adjacent lids.

References Cited by the Examiner UNITED STATES PATENTS 420,524 2/ Wheeler 113-42 968,122 8/10 Carr 83-55 1,809,040 6/31 Husler 83-691 1,879,555 9/32 Simmons. 2,232,742 2/41 Smith 83-55 2,313,801 3/43 Carll 83-691 2,392,459 1/ 46 Cassalino 83-620 2,474,391 6/49 Bergstein 18-56 2,485,238 10/49 Hickok 18-56 2,487,271 11/49 Petri 83-98 2,625,223 1/53 Lund. 2,884,150 4/59 Weichselbaum 215-41 2,897,892 8/ 59 Duenke 83-620 2,949,204 8/60 Edwards 215-41 2,998,740 9/61 Gutzmer 83-620 3,021,001 2/62 Donofrio 206-56 9,770 9/92 Great Britain. 516,051 12/39 Great Britain.

ANDREW R. JUHASZ, Primary Examiner. EARLE J DRUMMOND, LEON PEAR, Examiners. 

9. APPARATUS FOR SERVING FROM A SHEET A CLUSTER OF CUP LIDS PREVIOUSLY FORMED IN THE SHEET COMPRISING A DIE HAVING A PLURALITY OF RECESSES ADAPTED TO RECEIVE SIMULTANEOUSLY THE LIDS FORMED IN THE SHEET, AND A PUNCH ASSEMLY MOVABLE TOWARDS AND AWAY FROM THE DIE AND HAVING A PLURALITY OF ENDLESS UNCONNECTED CUTTING EDGES COOPERATING WITH THE RECESSES FOR TRIMMING UNCONNECTED 